Honesty Rocks! truth rules.

What Is Jpeg?

HOME      >>       Graphics, Design & Animation


What is JPEG? Joint Photographic Experts Group (JPEG) format is commonly used to display photographs and other continuous-tone images in hypertext markup language (HTML) documents over the World Wide Web and other online services. JPEG format supports CMYK, RGB, and Grayscale color modes, and does not support alpha channels. Unlike GIF format, JPEG retains all color information in an RGB image but compresses file size by selectively discarding data. A JPEG image is automatically decompressed when opened. A higher level of compression results in lower image quality, and a lower level of compression results in better image quality. In most cases, the Maximum quality option produces a result indistinguishable from the original.


weird... i just learnt this today. came home to look on this forum, maybe post something about jpeg which has something more to pictures. then i found this! lol was kinda surprised. toook the words out of my mouth literatlly! well all i can do say is well done!

l337 Nurse Pedestrian

Joint Photographic Experts Group (JPEG)

Whoa, I never knew that. I was honestly thinking it had someting to do with cork boards.
Here's some others

.png Portable Network Graphics
.bmp bitmap
.gif something with compuserve
.html hyper text markup lang

I don't know much.


Also, I think that the way JPEG is compressed is that it selects similar colors depending on the threshold you give it, and makes thoses spots one color, then when the image is called up, those spots would have the same value.


JPEGs are very useful for compressing files and all but, if you think about it, GIFs aren't that much larger than them.


Wow, Compuserve!I completely forgot about Compuserve. Maybe if their service was as good as their Graphics Format they would still be around.Actually, I didn't even think anyone here was old enough to remember Compuserve!lol vujsa


gif stands for Compuserve Graphics Interchange


Let me go nick some quotes about JPEG and GIF off my favourite search engine... GOOGLE!!!

Joint Photographic Experts Group. A bunch of people who sat down and designed a standard for image compression, conveniently titled "IS 10918-1 (ITU-T T.81)". This standard works particularly well for 24-bit color photographs. C-Cube Microsystems came up with the JFIF standard for encoding color images in a file. Such a file is what people commonly refer to as "a JPEG" and typically ends in ".jpg" or ".jpeg". The main problem with JFIF files is that they only record 8 bits per color, a vastly smaller range of intensities than is present in the natural world and significantly smaller than the 12- and 14-bits-per-color signals that come out of the best digital scanners and cameras. This defect and more are remedied in the JPEG 2000 standard. See https://jpeg.org/ for more about the standard.

This is about JPEG... Then the next will be... GIF!

Graphics Interchange Format is the most common format for graphic images on the Internet. This highly-compressed format is used to display 2-dimensional raster images. A newer version, GIF 89a allows for an animated GIF, which is a short sequence of images within a single GIF file. GIF files are generally not used for photographs on the Web; JPEGs are optimized for that purpose.

There! I hope this is all correct... I read through most of the terms before I found a suitable one...


GIFS larger than JPEGs? I think not.GIF files don't exactly use a compression algorithm. Instead, they use a selective color palate to reduce the data inside the file. Hence, most GIFs are limited to 256 colors (8 bits), but that's it. JPEGs on the otherhand are granted 8-bits per channel, which results in millions of colors. This is why GIFs are good for simple web graphics, but not for photographs, and why JPEGS are great for photographs, but overkill for web images.Kind of a pointless addition to the thread, but it irked me the wrong way.


Well, because Iâm a loser and actually browse Wikipedia for fun, I browsed through some of the common image formats and took some of the passages thag I found are most informative and put them together, with each Iâll give you the summary and also the quotes if you want more indepth information (or you are just plain bored)

.jpg is basically used on web graphics only because it contains the best compression thus saving space as well as bandwidth, however because it compresses so well it also produces images that are less desirable.

JPEG is a commonly used standard method of compressing photographic images. The file format which employs this compression is commonly also called JPEG; the most common file extensions for this format are .jpeg, .jfif, .jpg, .JPG, or .JPE although .jpg is the most common on all platforms.

The name stands for Joint Photographic Experts Group. JPEG itself specifies only how an image is transformed into a stream of bytes, but not how those bytes are encapsulated in any particular storage medium. A further standard, created by the Independent JPEG Group, called JFIF (JPEG File Interchange Format) specifies how to produce a file suitable for computer storage and transmission (such as over the Internet) from a JPEG stream. In common usage, when one speaks of a "JPEG file" one generally means a JFIF file, or sometimes an Exif JPEG file. There are, however, other JPEG-based file formats, such as JNG.

JPEG/JFIF is the most common format used for storing and transmitting photographs on the World Wide Web. It is not as well suited for line drawings and other textual or iconic graphics because its compression method performs badly on these types of images.

.png is a pretty new format on the graphics scene, it is not supported by IE and only by Firefox back in the day (actually not too long ago) thus it was popular for Firefox zealots in forums to make a transparent signature and save it in .png form followed by the quote âif you cannot see the transparency get Firefoxâ or âyou use IE, you are a loserâ Its got relatively good compression as well as very good results, the .png is sometimes seen as the replacement of the .gif

PNG (Portable Network Graphics), sometimes pronounced as "ping", is a relatively new bitmap image format that is becoming popular on the World Wide Web and elsewhere. PNG was largely developed to deal with some of the shortcomings of the GIF format and allows storage of images with greater color depth and other important information.

PNG uses a non-patented lossless data compression method known as deflation. This method is combined with prediction, where for each image line, a filter method is chosen that predicts the colour of each pixel based on the colours of previous pixels and subtracts the predicted colour of the pixel from the actual color. An image line filtered in this way is often more compressible than the raw image line would be. On most images, PNG can achieve greater compression than GIF, but some implementations make poor choices of filter methods and therefore produce unnecessarily large PNG files.

The GIF file format has allowed portions of images to be transparent, allowing them to appear to have a shape that is not rectangular. However, the GIF method was considered to be insufficient because it only allowed individual pixels to be fully transparent or fully opaque. The PNG format allows two different styles of transparency: binary transparency (in which each pixel is fully transparent or fully opaque), or alpha channel transparency, in which each pixel has an 8-bit numeric value representing a partial transparency. After the introduction of the PNG format, it took a long time for web browsers to fully support alpha channel transparency. Binary transparency is still more widely supported than alpha channel transparency as of 2005. For example, Microsoft Internet Explorer (for Windows) supports binary transparency but not alpha channel transparency (IE can actually be made to render alpha channel pngs properly but does not do so when the image is included in the normal way).

.gif is once considered the best graphics format, it allows for animation, transparency, as well as very good resuts. It also compress color better then .jpg, the tradeoff is its some what larger in comprasion to .jpg files.

GIF (Graphics Interchange Format) is a bitmap image format that is widely used on the World Wide Web, both for still images and for animations.

The format was introduced in 1987 by CompuServe in order to provide a color image format for their file downloading areas, replacing their earlier RLE format which was black and white only. GIF became popular because it used LZW data compression, which was more efficient than the run-length encoding that formats such as PCX and MacPaint used, and fairly large images could therefore be downloaded in a reasonable amount of time, even with very slow modems.

The optional interlacing feature, which stored image scanlines out of order in such a fashion that even a partially downloaded image was somewhat recognizable, also helped GIF's popularity, as a user could abort the download if it was not what was required.

GIF is widely believed to be limited to 256 colors though this is not strictly true.

Even with the general adoption of broadband, the size of downloads continues to be a critical issue on the world wide web. Large web pages have a negative effect on user experience by being slow to render. Large web pages are also more expensive for their owners who pay by the megabyte once traffic has passed a certain level. Therefore GIF's compression makes it desirable as an image format for use on webpages.

GIF is the only widely used image format to support animation. It is frequently used to make small animations and short, low-resolution films for web pages.

Most web page logos and design element images are GIF or PNG because those are designed to successfully compress images that contain large blocks of the same color or of repeating patterns; JPEG cannot compress areas of flat, clean color well.

.bmp is not compressed, which is its problem, it is largest of all image files mentioned here, therefore its really not used as often anymore.

.BMP or .DIB (device-independent bitmap) is a bitmapped graphics format used internally by the Microsoft Windows graphics subsystem (GDI), and used commonly as a simple graphics file format on that platform.

Images are generally stored with a color depth of 2 (1-bit), 16 (4-bit), 256 (8-bit), 65,536 (16-bit), or 16.7 million (24-bit). An alpha channel (for transparency) may be stored in a separate file, where it is similar to a greyscale image. 8-bit images can also be greyscale instead of color.

BMP files are usually not compressed, so they are typically much larger than compressed image file formats for the same image. The typical true-color bitmap size in bytes can be calculated as: (width in pixels)Ã(height in pixels)Ã3. So an 800Ã600 image will occupy almost 1.5 megabytes. As such they are generally unsuitable for transferring images on the Internet or other slow or capacity-limited media. Compressed imaged employ RLE algorithm.

All quotes came from en.wikipedia.org


I don't like using jpegs, I like GIF's alot better (Graphics Interchange Format) You can play animation clips on it, so I think they are a easier, and better picture format.


I actually use .jpg a lot for forum signatures/avatars, for layout stuff I usually use .png just to screw with the IE users, i mean if you use IE, don't come along onto my site ;D


Who uses IE? I use Opera it is way better and WAY more stable.


well according to w3school's statistcs, about 85% of the population uses IE while the rest uses all the other browsers from Konquer to FirefoxWhat I don't like about Opera is the pay feature, I don't want to pay, i'm cheap like that so I use Firefox, I think this pay stuff is going to be the fall of Opera


If you don't want to pay just get a serial from the web not to mention you can download it and use it for free (But you get ALOT of advanced fetures if you pay which are highly advanced spam, virus, trojan, popup blocker/killer which is what keeps my XP alive )


well that is true, however i feel bad every time I try and get crack or w/e. So I don't do things like that.Yes those advance controls sounds great but Firefox also have it so i'm not missing out much


Good information! By the way, speaking about extensions as jpeg, jpg, gif, bmp, png, etc and of not paying; please, someone might recommend to me some good free soft to work images and to turn from a format to another?


uhh just use paint and change the extension yourself eg .jpg save it as a .bmp etc